This book explores the often controversial international large-scale assessments (ILSAs) in education and offers research-based accounts of international testing as a social practice. Assessment exercises, such as the Organisation for Economic Co-operation and Development's Programme for International Student Assessment (PISA), produce comparable international statistics and rankings on educational performance, and are influential practices that shape educational policy on a global scale. The chapters in this volume, written by expert researchers in the field, take the reader behind the scenes to document a broad range of ILSA practices - from the recruitment of countries into ILSAs, to the production and performance of large-scale testing, and the management, media reception and use of test data. Based on data that is only available to expert researchers with inside access, the international case study material includes examples from Australia, Ecuador, Germany, Japan, Mexico, Norway, Russia, Scotland, Slovenia, Sweden, the UK and the USA. The volume provides important insights for teachers, researchers and policy-makers who use and study assessment data and who wish to evaluate its significance for educational policy and practice.